Apparatus for separating or concentrating ores



D. COLE.

APPARAIUSFOR SEPARATING 0R GONCENTRATING ORES.

APPLICATION FILED DEC-4.19I5.

APPLICATION FILED DEC4,19|5..

Patented Oct. 21, 1919.

3 SHEETS-SHEET 2.

s u m o 0 i 6 d 9 o ,mw 7 M am u c 111111111 :Guzl Uw. -l am n M .JF .l U

5 H. A n om U, l U, 1 in am Wn I J I b 6 8 4. 2 a W.

D. COLE.

APPARATUS FOR SEPARATING on CONCENTRATING ORI-s.

APPLICATION FILED DEC\4. \9l5.

lzllcntwl Wt. 21,1919.

3 SHEETS--SHEET 3.

Syvum/Lio@ UNITED sTATEs PATENT oEEicE.

DAVID COLE, yF EL PASO, TEXAS.

APPARATUS FOR SEPAEATING 0R CONCENTRATING DRES.

Specification of Letters Patent.

Patented Oct. 21, 1919.

Drignal application filed August 3, 1915, Serial No. 43,442. Divided and this application filed Decembernfi,

1915. Serial No. 64,992.

To all lwhom t may concern.'

Be it known that DAVID COLE, a citizen of the United States, residin at El Paso, in the county of El Paso and tate of TeXas, have invented or discovered certain new and useful Improvements in Apparatus for Separating or Concentrating Ores', of which the following is a specification, reference being -had therein to the accompanying drawlngs.

This invention relates to the hydraulic classification, separation, or concentration of ore and the like, and more particularly to hydraulic separators adapted for (although not limited-to) use in connection'with that process known as frothing,classification, the

latter being an amplification of the well knownflotation method.

The invention has for its general object the preparation of theJ rejections of the flotation treatment in such a Way that maX- imum recoveries may be made by the usual gravity methods upon the grains and sizes in the pulp which were not within the range of', and were not susceptible to, recovery by flotation treatment. Grains which will pass a `screen having ten thousand openings per square. inchwill be within the possible range of flotation recovery, but substantially all grains coarser than this size will not be within the range of recovery by flotation.

The mineral grains constituting the product separated and recovered by iiotation methods are so fine that substantially ninetyfive per cent. of them will pass through a screen having forty thousand apertures per square inch. Therefore the range of flotation sizes is substantially limited to the` minus one hundred mesh sizes e., ten thousand holes per square inchl above referred to) and since it is impracticable commercially to reduce all of the ore to be .treated to this very fine state of division it l is necessary either to separate the -flotation .treatment sizes from the gravity treatment sizes and treat them separately, or to so prepare the combined sizes during flotation treatment that the gravity treatment to follow will not be embarrassed in making maX- imum recoveries upon sizes of grains in the pulp which are amenable to gravity treatment, this preparation constituting the frothing classification process.

In accordance with the lastnamed proc- 'barrass the apparatus and ess the material to be subjected to the treatment is pulverized in the presence of water and usually also small amounts of oils and the like to a size which will. yield the best commercial recovery, and the resulting pulp is introduced into a suitstreams of Very. small bubbles which expand in size as they rise toward the surface of the pulp in the tank, carrying with them the `particles of mineral which have greater affinity for air than for water, and which are suliiciently finely divided to be enveloped in the films of the bubbles and be carried by therising air, thereby forming a mineral froth above the surface of the pulp in the upper part of the tank, which froth, with its load of mineral, builds a column high enough to overflow the edges of the top of the tank; while the particles of ore which have more aflinity for water than for air, together with lthe particles too large to be lifted by the bubbles will find theirway to the bottom ofi the tank and be withdrawn therefrom.

The prqcess is usually carried on continuously, the pulp flowing into the tank at a suitable rate, the-froth with its content of fine mineral being continuously discharged in the mineral froth at the top of the tom of the tank.

In order that such apparatus of the previous art may operate properly and not become clogged4 it is necessary that the ore or other material being treated be all of a certain degree of fineness. It is therefore necessary that said material be either carefully pulverized primarily to a very even degree and sufliciently fine, or else that said material be screened or receive other previous treatment for removing the coarser particles, or oversize which would elnwould tend to clog it. It is one of the obie'cts of the present invention to provide means, associated with a flotation or frothing classifier itself, for automatically removiii'- the oversize, such removal -being eecte' during and in connection with the normal operation of the apparatus, thus preventing embarrassment to the operation and making it possible to apply the flotation or frothing process primarily in the treatment of ores in a much coarser state of reduction, that is to say, to the ordinary mill run, without subjecting the same to previous screening or other treatment for the purpose of protecting the frothing machine. In carrying out this feature of the invention the separating tank is preferably provided with one or more classifying cones each having an outlet and an inlet through which hydraulic water is introduced, said water driving or holding back material of a predetermined fineness (depending upon the form of chamber and pressureor velocity of the water so admitted) and permitting the oversize to pass out through the outlet, so that, by regulating the amount of hydraulic water admit-ted, the size and quality of material escaping may be controlled and varied, thus accomplishing, by the mere regulation of an inlet valve, a result which, in the case of mechanical separation, would require the complete changing of screens or other troublesome operations.

In the flotation separation of ores and the like it is found to be advantageous to subject the material under treatment to more than one passage through the apparatus, and the present invention accordingly has for a further object the provision of a froth-.

ing classifier which provides in a simple and efiicient manner for ,the repeated treatment of the material, said apparatus comprising a series of tanks or compartments l' and means whereby the material is automatically transferred from one of said tanks or compartments to the next by gravity and without the necessity of pumping, said transferring means being of such a nature as not t0 interfere with the efficient operation of the apparatus. In carrying out this feature of the invention the transferring means is constructed and arranged to cooperate with the classifying cones in such a manner as to materially assist the operation of the latter' and to reduce materially the amount of hydraulic water required for the proper separation of the oversize and returnable portion.

Additional objects of the invention are to provide a simple and convenient apparatus for frothing classification which combines efficiency of operation with economy in material required for its construction and of mill space necessary for its accommodation, said apparatus being provided with simple and effective means for making such adjustments as may be required by the conditions of use.

The foregoing and other objects of the invention, together with means whereby the same may be carried into effect, will best be understood from the following description of one form or embodiment thereof illustrated in the accompanying drawings. It will be understood, however, that the particular construction described and shown has been chosen for illustrative purposes merely, and 'that the invention, as defined bv the claims hereunto appended, may be otherwise practised without departing from the spirit and scope thereof.

In said drawings:

Figure 1 is a vertical sectional view of the classifier.

Fig. 2 is an end eleva-tion partly broken away of the apparatus shown in Fig. 1, as viewed from the left in the latter figure.

Fig. 3 is an end elevation partly broken away of the apparatus shown-in Fig." 1, as viewed from the right in the latter figure.

The apparatus herein shown comprises a series of tanks or compartments 14, 15, 16

supported by suitable uprights 17 said tanks 'or compartments being of any desired number (herein shown as three). Adjacent tanks of the series have common intermediate or dividing walls, while the several tanks are disposed in stepped arrangement, as shown, each succeeding tank or compartment being at a somewhat l"ower elevation than the preceding one. A suitable conduit 13 delivers the comlninuted material, together with an amount of water (introduced through branch pipes 49) sufficient to produce a mixture or proper consistency, into one or more feed pipes 18 which discharge into the first tank or compartment. The feed' pipes 18 are preferably provided at their lower ends with deflectors 19 which cause the streams to spread out into thin sheets for the purpose of preventing the formation of violent currents in the tank 14.

At a proper distance above the bottoms of each of the tanks 14, 15, 16, slots 20 are formed in the ends of said tanks, and secured to said ends adjacent said slots are manifolds 21 communicating with a suitable source of compressed air. The manifolds 21 of each tank support and communicatewith a series of horizontally disposed tubes 22 which extend throughout the length of the corresponding tank and form a tubular grating substantially covering the entire horizontal cross-sectional area of said tank at a point lsuitably elevated above the bottubes 22 aretoo small toallow solids to enter from the outside, under hydraulic pressure when the air pressure is cut olf, as would occur 1n the case of a perforated pipe or the.A

cie-nt distance to permit easy downward passage between them of the pulp and water under treatment, while being sufficiently close together to provide for the thorough aeration of the contents of the tanks above them. The outlet from each tank, as will 'presently be more fully described, is at the bottom thereof, while the tubes 22, as above explained, are located some distance above the bottom. By this arrangement, as also by reason of the spacing of the tubes 22 as 'above described, all violent downwardcurrents or vortices in the vicinity of said tubes, tending to draw the bubbles downwardly, are avoided, and all possibility of improper discharge of the iner material from the bottom of the tank reduced to a minimum. The construction of the tubes 22 is preferably such as to permit a discharge of air-throughout their` circumference, thereby providing a greatly increased air emitting surface, and, at the same time, free downward passages for the liquid. as above explained. By virtue 0f this form and arrangement all possibility of such accumulation of sediment as would clog the exterior of the tubes and interfere with the proper discharge of air therefrom is prevented, it being obvious that, even though the entire upper surfaces of the tubes were covered by deposits, there would still be left a total unobstructed air emission surface equal to or greater than the entire transverse are'a of the tank. notwith standing the passages between the tubes.

The bubbles from the tubes 22 pass upwardly through the tanks, combing out and carrying with them the finer particles of material, particularly metallic sulid, and form in the upper part of said tanks bubble or froth columns which overflow into a launder 46 arranged to discharge the vfroth with its content of ne material at any suitable point. For the purpose of leading the material from one tank or compartment to the next for. successive treatment the transfer tubes 23 are provided. Said transfer tubes are preferably of the S-shaped form shown. pass through the wall separating adjacent tanks or compartments at points below the tubes 22 of the upper tank, and are preferably flattened laterally, as shown in Figs. 2 and 3 in order to oppose the least possible resistance to the upward passage of the bubbles in the lower tank. Each tube is arranged with its inlet adjacent the bottom of the tank from which it discharges and with its outlet in the upper portion of the next adjacent tank, the difference in elevacient hydrostatic head to force the material from the lower part of one tank by gravity.

Arranged adjacent the outlet of each transfer tube 23 in each of the tanks 15 and 16 is a valve 241 carrying a deflector similar tothe deflector 19. The deflector valves 21 are adj ust-able with respect t-o the outlets of the tu'bes 23 and are carried b'y stems 25 supported at their upper ends by beams 26. As shown in Figs. 2 and 3 a plurality of transfer tubes 23 is preferably provided for discharging material from each tank to the next succeeding, and the deflector valves 24 in each tank are supported from a single beam 26'. Each of the beams 26 is. provided at each end with a threaded stem 27 A cooperating with a hand -wheel 28 supported by a bracket 29 suitably secured in stationary position, as to the launder 46. By operating the hand wheels 28 of any pair the deflector valves 24 of any tank may be simultaneously adjusted, thereby providing for an even flo-W through all of the transfer tubes 25 discharging into said tank. l Secured tothe bottom of the tank 14 adjacent the inlets of the corresponding transfer tubes 23 are classifying cones 30, said classifying cones being preferably in the form of separate castings bolted in position to the bottom of said tank adjacent suitably formed openings in said bottom. Each of the classifying cones 30 is formed at its top with a depression 31 into close proximity to which extends the inlet end of the corresponding transfer tube 23, said end being preferably of the flaring-or conical form shown and of a diameter at its bottom slightly less` than the diameter of the depression 31. Thebottom of the depression 31 is provided with an opening in which is A located a coarse screen or perforated plate 32, said opening leading to a chamber 33 which communicates through a bushing 34 with a second chamber 35 provided with an outletBG. Communicating with the chamber 35, preferably at a point above the 'bottom of the 'bushing 34, is an inlet pipe 37 for hydraulic Water, said pipe being controlled by a suitable valve 38.

ln the operation of the apparatus, considered with respect to each classifying cone and the corresponding transfer tube, the water in the tank 14,' together with the material not carried away by the bubbles,

reaches. the bottom of said tank and is dis,

through the pipe 37, under a predetermined pressure regulated by the valve 38, passes lio x-znvardly through the. iushing 34. chamber and perf-.irate-:l plate said plate diffusing the. upward current), a part of said water. of course, passing downwardly and being discharged through the outlet 36. The adjustment of the valve 38 is such that,

in addition to the hydraulic water discharged tl'irough the outlet 36, a sufficient' ment of the transfer tubes Q3 with reference to tle classifying cones. The material in the tank 14 gravitates to the points indicated by A in Fig. 1 where the swift current due to the constricted opening carries the same horizontally toward the center of the funnelshaped inlet wardly into said tube upon reaching the enlarged chamber in the bell mouth of the transfer tube. vThe oversize tends to separate out and fall into the chamber 33. This tendency is opposed b-y a gentle upward current composed in part by the hydraulic water flowing upwardly through the ybushing 34 and perforated plate 3Q, and in part by the lessened speed of upward flow into the transfer tube, caused by its bell shaped construction, so that said material, minus its oversize particles, after more or less circulation, passes upwardly into the mouth of the transfer tube 23. By this arrangement of parts, enabling the transfer tubes 23 to assist the hydraulic water in carrying away the finer material, very much less hydraulic water is necessary'than would otherwise be required, this being a very de,-

sirable feature inasmuch as the hydraulic water tends to dilute the pulp and to interfere with the frothing operation in the next tank. It will of course be understood that the size of material discharged through the outlet 36 will be dependent upon the pressure at which the hydraulic water is admitted through the pipe 37, and this may be regulated at will, and in accordance with requirements, by means of the valve 38.

Ordinarily one set of classifying cones will serve to remove all of the oversize discharged into the tank 14, practically none passing through the next tank. For this reason, as herein "Shown, the lSttank 14 only is provided with classifying cones, theother tanks 15, 16 etc. being provided at the corresponding points with normally closed cup-shaped castings 43' into which the inlet ends of the tubes 23 depend.

,corresponding transfer any 0r all of the If desirable, however,

of the transfer tube and 11p-until the level ofv the mouth of the transfer tubes 23 into tanks 15, 1G, etc., may be provided with classifying cones 30 in place of the castings 43. In the latter case, by varying the pressure of the hydraulic water admitted to the classifying cones of succeeding tanks, material of different and successively graded sizes may be removed from the successive tanks.

The tailing leaving the last tank 16 throughl the last transfer tube Q3 is discharged to any suitable point through a pipe 44 controlled by a suitable Vvalve 45.

'The complete operation of the apparatus is as follows. In starting the operation clear water is first introduced into paratus through the feed pipes 18. As soon as the Water in the first tank or compartment 14 reaches the level indicated by the the apflector valves`24 through the wheels 28, as

well as by adjustment of the valves 45 of the final outlets, the surface of the liquid is causedito rise above the deflector valves 24 to or adjacent the tops of the tanks as may be desired. After a proper balance has been established the mill is started and substantially the same volume of pulp to be treated is substituted for the clear water.

On account of the presence of the solids transported by the water, and because of the colloidal and other matter in the pulp which will produce froth, additionaladjustments, such as the opening or closing of the deflector valves 24 and discharge valves 45, the admission of a greater or less amount of air through the tubes 22, etc. areusually necessary in order to establish a. new condition of equilibrium, after-which no other adjustments are necessary under normal and even conditions for use. The finest particles of metallic sulfids in the pulp are discharged with the froth from the top of the tanks into the launder 46, the coarser particles bothsilicious and metallic find their way to the bottoms of the tanks', aretransferred through the tubes 23 from one tank to the next for successive treatment, and are finally discharged through the pipes 44, while the oversize is discharged through the classifying cones 30.

The tubular gratings and associated parts herein shown and described for the purpose of admitting .air to the several tanks or compartments are not claimed herein, being l covered by the claims of a prior application filed by ine August 3, 1915, Serial No. 43,442, of which this case-'iris a divisiom Y.

Having thus fully described myfinvention what I claim as new and desire'to secure by Letters Patent is 1. In a hydraulicclassieig a tank, avplurality of inlets for said tank, defiector valves for controlling said inlets and distributing the incoming material, and means for simultaneously adjusting allof said detiector valves. v

2. A. hydraulic classifier comprising a plurality of tanks or compartments, a plurality of transfer tubes leading from the bottom of a tank or compartment tothe upper part of the next adjacent tank or compartment, deiector valves for controlling the discharge from said tubes and distributing the incoming material, and means for simultaneously adjusting all of the defiector valves in each tank. 4

3. In a hydraulic classifier, a tank, a plu# rality of inlets for said tank, deflector valves for controlling said inlets and distributing the incoming material, said valves beine provided with stems, a beam by which all of said stems are supported, and means for adjusting said beam.

a. In a hydraulic classifier, a tank, a plurality of inlets for said tank, detlector valves for controlling said inlets and distributing the incoming material, said valves being provided with stems, a beam by which all of said valve stems are supported, threaded stems at the ends of said beam, stationary brackets through which said threaded stems pass, and hand wheels on said threaded stems and engaging said brackets for'adjusting said beam.

In' a hydraulic classifier, in combination, a tank having an opening in its bottom, a classifying' cone comprising a casting secured to the bottom of said tank adjacent said opening, said classifying cone having upper and lower chambers and a bushing connecting said chambers, and said lower chamber having an outlet in its bottom and a Water inlet located above the bottom of said bushing, and a discharge tube for said tank having its inlet arranged immediately over said classifying cone.

6.'In a hydraulic classifier, in' combina tion, a tank, a classifying cone co1nmunicating with said tank and having a water inlet and an outlet, a perforated plate at the top of said classifying cone, and a discharge tube for said tank having its inlet arranged adjacent said perforated plate.

A7. In a hydraulic classifier, in combination, a tank having an opening in its bottom, a classifying cone comprising a casting secured to the bottoni ofv said tank adjacent said opening, said classifying cone-having a depression in its'top, upper and lower chambers, a perforated plate between said depression and upper chamber and a bushing connecting said upper and lower chainbers, said lower chamber having an outlet in its bottom and a water inlet located above the bottom of said bushing, and a discharge tube for said. tank having a downwardly iiaring lower end arranged adjacent said depression. v

,In testimony whereof I aiiix my signature.

' DAVID COLE. 

